Pulse Analyzer (Option 421)
2-14 Setting Up Triggering
Pulse Analyzer MG
PN: 10580-00451 Rev. A
2-29
2-14 Setting Up Triggering
Trigger parameters are set using the
TRIGGER Menu
SOURCE:
The SOURCE button offers several triggering options depending on which
view mode the instrument is set:
• Free Run:
A new sweep is started immediately upon completion of the current
sweep. No trigger event is required to initiate a sweep.
• Video:
When enabled, the trigger level will be indicated graphically on the display
with a horizontal VIDEO line. A new sweep is started when the input video level
meets the value set via the LEVEL button. The level can also be adjusted by
dragging the VIDEO line up or down. Video triggering is useful for monitoring a
known time position and its transients, such as pulsed signal rise or fall times.
• External 1 or 2:
A TTL signal applied to the selected External Trigger MCX input
connector causes a single sweep. After the sweep is complete, the resultant trace
is continuously displayed until the next trigger signal is received.
LEVEL:
Used when the trigger source is set to Video. Sets the video trigger level
threshold that initiates a sweep. The level crossing applies to rising or falling edges. Use
the hysteresis setting below to adjust the sensitivity of the trigger level.
HOLDOFF:
Available only when the trigger source is set to External or Video. When
toggled on, the analyzer waits the user defined amount of time to re-arm the trigger
between trigger events. If a trigger event is received after the previous trigger, but before
the holdoff time has elapsed, that trigger event will be ignored.
PERIODIC:
Used to set a periodic sweep trigger. When toggled on, the instrument waits
the set time to start a sweep.
SLOPE:
Used when the trigger source is set to External or Video. Sets the trigger slope
to rising or falling edge.
HYSTERESIS:
Hysteresis is used to address noisy trigger signals. The hysteresis
setting adjusts the sensitivity of the trigger system (the difference between the firing level
and the arming level as shown in
). A low hysteresis value sets the arming
and firing levels close to each other, meaning a small signal change will cause a trigger. A
large hysteresis value sets the arming and firing levels far apart, meaning a large signal
change will be required to cause a trigger.
Figure 2-27.
TRIGGER Menu in Pulse Analyzer mode
Summary of Contents for Field Master Pro MS2090A
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